渐进性咬合紊乱导致猴颞下颌关节骨关节病的实验研究初探

The preliminary study on the effect of gradually induced disordered occlusion on temporomandibular joint in monkey

目的:探讨渐进性咬合紊乱对颞下颌关节的致病意义。方法:4只成年猴,2只实验组,2只空白对照组。实验组猴拔除一侧上颌第一磨牙和对侧下颌第一磨牙,将所拔牙邻牙向拔牙缺隙处对牵,造成局部上下咬合关系不密合,分别于6、8个月后取双侧颞下颌关节作HE染色,组织学观察。结果:主要变化是实验6个月时髁状突肥大层细胞增殖活跃,但软骨层变薄;8个月时髁状突表面软骨层变得更薄,且各层排列紊乱,表面纤维增生,并形成纤维乳突状结构跌入深层组织,肥大带变薄或消失,仅可见散在的软骨细胞或细胞团,骨小梁排列紊乱,并观察到显微骨折现象。关节盘后带见到软骨细胞团和钙化现象。关节窝变化较小。结论:初步论证了“渐进性咬合紊乱可以导致猴颞下颌关节退行性变”的观点,但尚需扩大样本进一步证实。

砄bjective:To investigate the effects of gradually induced disordered occlusion on temporomandibular joint in monkey.Method:After extraction of two molars,one on each side,upper and lower,a fixed orthodontic appliances was used to cause the two adjacent teeth inclined to the space and to occlude with opposite in coordinately.6 and 8 months later,the animals were sacrificed and the temporoman dibular joint of the experimental monkeys were examined with histologic methods.Result:At the end of 6th month,proliferation of the cells in chontrocyte layer was strong but the hypertrophy layer became thinner.At the end of 8th month,the whole cartilage layer thinned and arranged disorderly and even dropped towards the deep layer forming a fibrous papillary structure.The hypertrophy layer thinned or disappeared.Micro fracture of subchondral bone,clustering of chondrocytes in the disc and mineralization of the disc were also found.Less change was found over the temporal articular surface.Conclusion:Gradually induced disordered occlusion may result in degenerative changes in temporomandibular joint.